radeonsi: Geometry shader micro-optimizations

Move parameter loads out of loops, and use the instruction offset
instead of a VGPR for the vertex attribute offset when writing to the
ESGS ring buffer.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 2f9993c4c8ef52793ccc866fd8f98b87af2ea376..5b95c11580fa1a9e15b79c47964e7c75b21c245e 100644 (file)
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -842,6 +842,9 @@ static void build_tbuffer_store(struct si_shader_context *shader,
                LLVMConstInt(i32, tfe, 0)
        };
 
+       /* The instruction offset field has 12 bits */
+       assert(offen || inst_offset < (1 << 12));
+
        /* The intrinsic is overloaded, we need to add a type suffix for overloading to work. */
        unsigned func = CLAMP(num_channels, 1, 3) - 1;
        const char *types[] = {"i32", "v2i32", "v4i32"};
@@ -1179,6 +1182,8 @@ static void si_llvm_emit_es_epilogue(struct lp_build_tgsi_context * bld_base)
        struct si_shader *gs = si_shader_ctx->gs_for_vs;
        struct tgsi_parse_context *parse = &si_shader_ctx->parse;
        LLVMTypeRef i32 = LLVMInt32TypeInContext(gallivm->context);
+       LLVMValueRef soffset = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn,
+                                           SI_PARAM_ES2GS_OFFSET);
        LLVMValueRef t_list_ptr;
        LLVMValueRef t_list;
        unsigned chan;
@@ -1216,20 +1221,14 @@ static void si_llvm_emit_es_epilogue(struct lp_build_tgsi_context * bld_base)
 
                for (chan = 0; chan < 4; chan++) {
                        LLVMValueRef out_val = LLVMBuildLoad(gallivm->builder, out_ptr[chan], "");
-                       LLVMValueRef voffset =
-                               lp_build_const_int32(gallivm,
-                                                    (4 * gs->input[j].param_offset + chan) * 4);
-                       LLVMValueRef soffset =
-                               LLVMGetParam(si_shader_ctx->radeon_bld.main_fn,
-                                            SI_PARAM_ES2GS_OFFSET);
-
                        out_val = LLVMBuildBitCast(gallivm->builder, out_val, i32, "");
 
                        build_tbuffer_store(si_shader_ctx, t_list, out_val, 1,
-                                           voffset, soffset, 0,
+                                           LLVMGetUndef(i32), soffset,
+                                           (4 * gs->input[j].param_offset + chan) * 4,
                                            V_008F0C_BUF_DATA_FORMAT_32,
                                            V_008F0C_BUF_NUM_FORMAT_UINT,
-                                           1, 0, 1, 1, 0);
+                                           0, 0, 1, 1, 0);
                }
        }
 }
@@ -1901,6 +1900,8 @@ static void si_llvm_emit_vertex(
        struct si_shader *shader = &si_shader_ctx->shader->shader;
        struct gallivm_state *gallivm = bld_base->base.gallivm;
        LLVMTypeRef i32 = LLVMInt32TypeInContext(gallivm->context);
+       LLVMValueRef soffset = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn,
+                                           SI_PARAM_GS2VS_OFFSET);
        LLVMValueRef gs_next_vertex;
        LLVMValueRef t_list_ptr;
        LLVMValueRef t_list;
@@ -1936,9 +1937,6 @@ static void si_llvm_emit_vertex(
 
                for (chan = 0; chan < 4; chan++) {
                        LLVMValueRef out_val = LLVMBuildLoad(gallivm->builder, out_ptr[chan], "");
-                       LLVMValueRef soffset =
-                               LLVMGetParam(si_shader_ctx->radeon_bld.main_fn,
-                                            SI_PARAM_GS2VS_OFFSET);
                        LLVMValueRef voffset =
                                lp_build_const_int32(gallivm, (i * 4 + chan) *
                                                     shader->gs_max_out_vertices);